South Korean President Moon Jae-in holds his New Year press conference at the presidential Blue House in Seoul, Thursday. (Jung Yeon-je/Pool Photo via AP)

South Korean President Moon Jae-in said on Thursday North Korea should take bold steps towards denuclearization, such as abandoning long-range missiles, to extract U.S. concessions amid a prolonged stalemate in their nuclear negotiations.

Moon Jae-in also said the North would have to seek a compromise in a second summit between North Korean leader Kim Jong Un and President Donald Trump, which he said could be imminent, in order to resolve the impasse.

Pyongyang and Washington have been struggling to find a breakthrough despite a pledge by Kim at his landmark summit with U.S. President Donald Trump in Singapore in June to work towards denuclearization.

Pyongyang has demanded Washington lift sanctions, imposed because of its nuclear and missile tests, and declare an official end to the 1950-53 Korean War.

Those demands were in response to Pyongyang’s initial, unilateral steps toward denuclearization that included dismantling its only known nuclear testing site and a key missile engine facility.

Moon said North Korea should take more concrete steps, such as abandoning its intercontinental and intermediate-range ballistic missiles and dismantling weapons production lines and other nuclear complexes, to secure U.S. concessions such as sanctions relief.

He said reducing U.S. military commitments, such as a withdrawal of troops or strategic assets from the region, would be an unlikely option for Washington.

“The second summit would be a venue where they settle on terms of what specific measures North Korea will take and how those moves will be reciprocated by the United States,” Moon told a news conference at the presidential Blue House in Seoul.

“But U.S. forces in South Korea or strategic assets in places like Guam and Japan are not linked with North Korea alone, as they exist for the stability and peace of the entire Northeast Asia,” he said.

Kim renewed his resolve to meet Trump again during his meeting with Chinese President Xi Jinping in Beijing this week. Moon said Kim’s latest trip to Beijing signaled that a second Trump summit was imminent.

Another U.S.-North Korea summit would also expedite an unprecedented visit by Kim to Seoul, planned for last year but delayed amid the nuclear standoff, Moon said.

“I expect we’ll hear about high-level talks between North Korea and the United States before long for their second summit,” Moon said.

U.S. Secretary of State Mike Pompeo made several trips to Pyongyang last year. However, a meeting between Pompeo and senior North Korean official Kim Yong Chol has yet to be rescheduled after an abrupt cancellation in November.

North Korean state news agency KCNA said on Thursday Kim and Xi held “in-depth, frank discussions” on the Korean peninsula and nuclear issues during Kim’s stay in Beijing, his fourth since March 2018.

Kim told Xi about the difficulties and concerns in improving North Korea-U.S. relations and denuclearization negotiations, KCNA said. Xi agreed that North Korea‘s reasonable concerns must be addressed properly, it said.

China’s official Xinhua news agency also said Pyongyang’s “legitimate concerns” must be taken seriously in order to achieve a comprehensive resolution on the Korean peninsula.

Xinhua quoted Xi as saying he hoped that North Korea and the United States could meet each other halfway and that the international community expected peaceful negotiations.

Kim reiterated a pledge from his speech last week that the North would try to make a second summit achieve a result that the international community would welcome, Xinhua said.

Wang Yiwei, a senior research fellow at the Center for China and Globalization, said he believed North Korea was becoming impatient and beginning to lose hope with the United States for asking it to make changes without in turn removing sanctions.

“The crux is how to let North Korea denuclearize and to give it security guarantees. On this, the United States and North Korea don’t have trust, so China has to act as a bridge,” Wang said.